My step-son is so excited getting ready for his school dance. He is taking the most popular girl at school and I must confess I am a little jealous. I took him out shopping last week. He looks amazing! He is in black slacks and a black and white pin stripped shirt. I talked him out of Axe and he bought him some Prada Infusion. I am having a glass of white wine and getting ready for my date when he comes to me very upset. His date is grounded and had to cancel. Like a good mom I called her parents and assured them he would have her home extra early but they said no. I suggested he go alone, I mean looking so handsome he will find girls to dance with but he is too upset.
I offer to cancel my date and stay home. My step-son has a better idea. I am flattered, surprised and well a little excited when he asks me to be his date. I am almost ready for my date and he says what I am wearing is perfect and everyone will be so jealous. Very few of his friends have met me so we just might be able to pull this off. I put on an auburn wig, and taller heels than normal. I am in a very tight short black dress showing off my curves. My son is beaming.
On the drive there he asks a favor of me. He suggests I really act like his date so no one will know it is his mom. Well he is only 15 so I can’t imagine anything he would want to do that would be inappropriate. He opens my door and we walk hand and hand. All his friends are looking in disbelief. He pulls me close now with his arm around my waist. He immediately pulls me out on the dance floor. I am enjoying dancing with him and I am thinking what a wonderful fun night we will have. I feel him pulling me closer, a bit too close. He whispers in my ear, “Mom please you promised everyone would think you were my date”. Feeling a little uncomfortable I let me pull me close. My big tits are pressed against his chest and my pussy is right against his very hard cock. I have to admit I am getting very wet. He moves his hand down and cups my ass, I try to protest but he again reminds me of my promise. I notice some of the couples are leaving.
My step-son explains how they are going outside to mess around. He takes my hand and leads me outside. Surely he doesn’t think we can pull off pretend sex. We are standing by a tree and I am feeling things I can’t even explain. He is my son, but he looks so good and I want to treat him just like I would a hot man I would be on a date with. I feel him reaching his hand in my dress and cupping my big tits. Oh god, that feels so good. His hand is lifting my dress and slipping inside my panties. I am dripping. I try to pull away but he reminds me again of my promise. I look around and see most of the girls on their knees giving blow jobs. I smile at him, lick my full lips and unzip his slacks. His cock is so hard and big, I had no idea. I am about to get on my knees and slide his yummy cock into my mouth but he seems to have another idea in his head. He spins me around and pushes me against the tree. My dress is above my hips and he is pulling my soaking panties down. I feel the head of his big cock against my ass and try to tell him no. He tells me quickly that all the girls do it as they want to keep their cherry. I can’t believe this is happening. I feel him rubbing the tip which is dripping with pre-cum against my tight pucker. He pushes in hard and fast with a grunt. His hands grab my tits as he fucks my ass hard, fast and deep till he cums. I helplessly look at him and tell him this must never happen again. He laughs and says “You know you wanted it as much as I did”. He kisses me deeply, like a lover not a son as we straighten our clothes and go back to the dance.
I knew for months you were going in my panty hamper. Sometimes you went for the worn and sticky ones but sometimes you went in my drawer and found clean ones. Auntie Debi loves you but you are such a dirty little boy. 
